1. Field of the Invention
This invention relates to a sheet material feeding apparatus mounted in a recording apparatus such as a facsimile machine, a photocopier, a printer, and so on and, more particularly, to a sheet material feeding apparatus for automatically feeding a sheet material sheet by sheet in a separated manner.
2. Description of Related Art
As methods for feeding sheet materials used in a recording apparatus., conventionally known are to manually feed the sheet materials sheet by sheet and to automatically and successively feed the sheet materials using an automatic feeding apparatus.
When the sheet materials are automatically and successively fed sheet by sheet using such an automatic feeding apparatus, a pawl separation method in which a separation pawl clamps front end corners of the sheet materials, a frictional separation method in which friction between the sheet materials and a sheet material stacking means renders the sheet materials separated, and the like are widely used as a separation method for sheet materials. In such a conventional method, various devises are made to reduce oblique feeding of the sheet materials during separation and feeding of the sheet materials.
Meanwhile in Japan, postcards such as New Year greeting cards, direct mails, various receipts in simpler forms, and the like are used in a large volume as communication means. The volume of those printed matters is so huge, while many recording apparatuses as of inkjet recording apparatuses are put in the market with photographic printing quality. Therefore, it is desirable for feeding apparatuses to feed postcards accurately.
For example, in an art disclosed in Japanese Unexamined Patent Publication (KOKAI) No. Heisei 7-165,338 (first prior art), the sheet materials are corrected from fed obliquely by partially separating a feeding roller from the sheet material during feeding of the sheet materials. In an art disclosed in Japanese Unexamined Patent Publication (KOKAI) No. Heisei 6-305,585 (second prior art), guide members are provided in corresponding to sizes of the sheet materials to eliminate occurrence of oblique feeding regardless size of the sheet materials.
However, with respect to the above prior arts, in the first prior art in which the sheet materials are corrected from fed obliquely by partially separating a feeding roller from the sheet material during feeding of the sheet materials, the separation means may create pressing traces on the sheet materials during separation operation of the feeding roller and the sheet materials, thereby raising a problem on quality in recording. In a case that the sheet material is a postcard, since the card is fed by a single feeding roller, separation of the feeding roller does not so work, and therefore the oblique feeding cannot be prevented enough.
In the second prior art in which the guide members are formed in corresponding to sizes of the sheet materials, a user has to manipulate different guide members according to the sizes of the sheet materials, and this mechanism renders usage of the apparatus worse and may invite improper manipulation.
This invention is to solve the above problems. It is an object of the invention to provide a sheet material feeding apparatus easily used in preventing any sheet material including a postcard from fed obliquely without adding any pressing trace and to provide a recording apparatus incorporating this feeding apparatus.